The invention relates to local-delivery devices and methods for treating and preventing proliferative and atherosclerotic vascular diseases in a living organism. More particularly, the invention relates to local-delivery devices coated with a composition comprising a sex hormone, anti-hormone, sex-hormone agonist, steroid-hormone inhibitor/antagonist (partial or full), selective estrogen receptor modulator (SERM), or a combination thereof. The local-delivery device, e.g. a stent, catheter or balloon-injection catheter in situ to coat the implanted stent, is inserted into an affected area of a living organism to treat or prevent the proliferative and atherosclerotic vascular disease.
Vascular diseases include diseases that affect areas of a living organism relating to or containing blood vessels. For example, stenosis is a narrowing or constricting of arterial lumen in a living organism (e.g., a human) usually due to atherosclerosis/coronary heart disease (CHD). Restenosis is a recurrence of stenosis after a percuteneous intervention such as angioplasty and stenting. Restenosis typically affects the large arteries of a living organism. The underlying mechanisms of restenosis comprise a combination of effects from vessel recoil, negative vascular remodeling, thrombus formation and neointimal hyperplasia. It has been shown that restenosis after balloon angioplasty is mainly due to vessel remodeling and neointimal hyperplasia and after stenting is mainly due to neo-intimal hyperplasia.
Treatment for stenosis and restenosis varies. Stenosis caused by CHD often forces individuals to restrict and limit their activity levels in order to avoid complications, stroke, heart attack, sudden death and loss of limb or function of a limb stemming from the stenosis. The reconstruction of blood vessels, arteries and veins may also be needed to treat individuals suffering from stenosis and restenosis. Coronary bypass can also be utilized to revascularize the heart and restore normal blood flow. In other cases, balloon angioplasty may be conducted to increase the orifice size of affected areas. Overall, these treatments address the problems associated with stenosis, but they also create a high rate of restenosis that can result in recurrence of cardiac symptoms and mortality. Moreover, these treatments are not preventative in nature, and therefore generally are not utilized until the patient or individual has already developed stenosis.
One type of stenosis and restenosis is atherosclerosis. Atherosclerosis affects medium and large arteries and is characterized by a patchy, intramural thickening that encroaches on the arterial lumen and, in most severe form, causes obstruction. The atherosclerotic plaque consists of an accumulation of intracellular and extracellular lipids, smooth muscle cells and connective tissue. The earliest lesion of atherosclerosis is the fatty streak that evolves into a fibrous plaque coating the artery. Atherosclerotic vessels have reduced systolic expansion and abnormal wave propagation. Treatment of atherosclerosis is usually directed at its complications, for example, arrhythmia, heart failure, kidney failure, stroke, and peripheral arterial occlusion.
New and improved methods and devices are being sought for treatment and prevention of vascular diseases such as stenosis, restenosis and atherosclerosis.
The present invention provides methods and devices for treating vascular diseases such as stenosis, restenosis and atherosclerosis.
More particularly, the present invention provides a method of treating or preventing restenosis in a living organism. The method comprises applying an effective amount of a composition comprising a sex hormone, anti-hormone, sex-hormone agonist, steroid-hormone inhibitor/antagonist (partial or full), selective estrogen receptor modulator (SERM), or a combination thereof, to a stent. The stent is inserted into an area of a living organism affected by restenosis. At least a portion of the sex hormone, anti-hormone, sex-hormone agonist, steroid-hormone inhibitor/antagonist (partial or full), selective estrogen receptor modulator (SERM), or combination thereof, is allowed to gradually release from the stent into the area of the living organism affected by the restenosis, thereby treating and preventing restenosis.
The invention also provides a local-delivery device for treating and preventing restenosis in a living organism. The device comprises a stent coated with a platform, natural carrier or pharmaceutical agent and an effective dose of a composition comprising estrogen, estradiol or a derivative thereof or combination of estrogen with other antiproliferative compound. Phosphoryicholine is one example of a pharmaceutical agent.
The platform, natural carrier or pharmaceutical agent at least partially encompasses the composition, thereby allowing for gradual release of the composition therefrom when the stent is inserted into an area of a living organism affected by restenosis.
The invention also provides another method of treating or preventing restenosis in a living organism. The method comprises applying an effective dose of a composition including estrogen, estradiol or a derivative thereof to a stent. The stent is inserted into an area of a living organism affected by restenosis in order to treat or prevent the same. At least a portion of the stent directly contacts the affected area.